Book excerpt: What makes men and women commit the most heinous crimes that mankind has ever witnessed? What exactly is it that tips themover the edge? More importantly, what can be done to stop them? Drawing on his years of professional expereince and extensive research, Larence J. Simon unearths uncensored data on fatal attacks on the unsuspecting citizens of the United States. This spine-chilling anecdotal account looks into the minds of the most vicious offenders presently behind bars. 'Murder By Numbers' offers an informed psychological perspective on serial killers and mass murderers that will intrigue and horrify.